Duchess Kate poses next to portrait of Queen Elizabeth II after its unveiling at a state reception at Government House in Wellington, New Zealand, on April 10. / Hagen Hopkins, AP

by Maria Puente, USA TODAY

by Maria Puente, USA TODAY

For her first dress-up affair of the royal tour Down Under, Duchess Kate turned to one of her favorites, British designer Jenny Packham, for a bespoke black dress embroidered with sparkly silver ferns on the left shoulder.

"Breathtaking," the Daily Mail called the long-sleeved column dress clinging to Kate's slender figure during an evening reception at Government House in Wellington, hosted by the queen's representative in New Zealand, Governor General Jerry Mateparae.

While Prince George slumbered upstairs with his nanny, the Duke and Duchess of Cambridge were feted at a grand reception for about 200 guests, including leading politicians and government officials of New Zealand.

Prince William, the future king, also met separately with Prime Minister John Key and opposition leader David Cunliffe of the Labor Party.

Will gave a short speech at the reception, including a few words in Maori and some joking about George's tendency to wail at 3 a.m. "I hope George doesn't keep you up," he said about his son, calling him a "bonny lad."

A longtime fan of New Zealand, Will called it "God's own country," and said he is eager to show Catherine, as he calls his wife, the island nation's charms.

Then they unveiled a new Diamond Jubilee portrait of his grandmother, Queen Elizabeth II, by young artist Nick Cuthell, commissioned by the New Zealand Portrait Gallery. In the painting, the queen is wearing her diamond-and-platinum fern brooch on loan to Kate who was wearing it when she arrived in New Zealand on Monday.

As they posed in front of the portrait, all eyes were on Kate and her dress, seen as a tribute to her Kiwi hosts thanks to Packham's use of New Zealand's national fern emblem as a dazzling beaded embellishment on what was a simple-but-chic dress. She wore Jimmy Choo suede pumps with a matching clutch.

The reception wasn't a tiara-required affair but it will be one of the most formal affairs of the tour. Also, Kate wore a substantial diamond bracelet and earrings set, believed to have been given to her by Prince Charles as a wedding present.

The party featured local wines (a wine-tasting excursion is on their schedule) and tasty delicacies to munch on while mingling, including oysters, lamb tarts, rabbit pies and custard tarts.

Earlier on Day Four of the royal tour, the couple left Prince George behind in Wellington and flew off to New Zealand's South Island on Thursday morning (Wednesday evening ET) to the town of Blenheim to commemorate World War I, chat with locals on a walkabout and hang out with Lord of the Rings director Peter Jackson.

Blenheim is the largest town in the Marlborough region in the northeastern part of the island and is named for the sprawling palace of Blenheim in England. That in turn is named for the 1704 Battle of Blenheim in Germany, led by John Churchill, the first Duke of Marlborough and an ancestor of both Winston Churchill and Will's mother, Princess Diana.

The couple laid a wreath at the WWI memorial in a solemn ceremony in the town center. The attached note: "Never forgetting those who have paid the ultimate sacrifice for our freedom," according to the many pictures posted on Twitter by reporters. Thousands of locals filled the town square, eager to see them as they greeted war veterans and other well-wishers in the crowd.

According to royal correspondents and Kate-tracking on bloggers Twitter, Kate was dressed in an cornflower-blue coat by Alexander McQueen, with a column shape, peplum detail and matching belt. She had on blue sapphire drop earrings, thought to have belonged to Princess Diana, and her hair was caught up in a wrapped ponytail that suited the windy, rainy weather.

Next, they went to a nearby aviation museum, the Omaka Aviation Heritage Center, where they toured the Knights of the Sky exhibit of WWI aircraft created by Jackson, who accompanied them on the tour and couldn't resist snapping smartphone pictures of Kate.